I also find that lack of team or company direction can lead to burnout as well as an absence of mentorship. When people don’t feel like they are growing, work can become stale. Perhaps it’s a little bit of burnout mixed with boredom, but at any rate, it leads them to not want to work there anymore.
https://codestory.co/podcast/compiler-recast-what-is-the-recipe-for-burnout/